Spread spectrum communications is presently being used for a number of commercial applications and is expected to proliferate as the demand for untethered communications increases.
For example, an orthogonal CDMA (OCDMA) system is discussed for an office PBX system by Magill et al. in "Spread-Spectrum Technology for Commercial Applications", Proc. of the IEEE, June 1994 (incorporated herein by reference). In this case, the base station of this star-configured network transmits a set of orthogonal Rademacher-Walsh (RW) functions which are overlaid with a pseudo-noise (PN) sequence. Each orthogonal function carries voice or data for a single user. See M. J. E. Golay IDA Report 108, pg. 110 (1965) which discloses this basic signal format.
The discussion by Magill et al, is for a short range system in which it makes sense to provide TDMA time slots on the return link for network members to transmit a signal for timing and synchronization purposes. In this manner, an empty slot is reserved for a member to enter the net at any time. This technique becomes inefficient and is not useful when the path lengths are long and the propagation time varies considerably between users, such as in a satellite system.